Multi-Millionaires are being handed tens of thousands of pounds a year by the Government to heat their mansions and swimming pools.

A member of the public is looking at a mural referencing to the Renewable Heat Incentive (RHI) scandal that brought down the government in Northern Ireland; photo Neill Carson/PA Wire

Wealthy owners of country estates are rewarded for using excessive amounts of heat – as long as it is made using ‘green’ energy.

Some are given as much as £50,000 every year in taxpayers’ money so the UK can meet renewable energy targets agreed with the European Union.

The House of Schivas estate (pictured) is under investigation after being paid thousands in subsidies to heat its swimming pool which it is said to have had on all the time

Rewards increase as the landowners use more heat, so profits can be maximised by turning up the temperature.

The House of Schivas estate in Aberdeenshire run by Lord Catto, 66, is under investigation after the Daily Mail found it has been paid thousands in government subsidies to heat its indoor swimming pool 24 hours a day.

A reporter was told the water was kept hot at all times, even in summer.

In another case an undercover reporter was advised by a green energy salesman to raise the heat in the pool at a country manor to take advantage of the system.

The extraordinary deals mean the wealthy landowners are guaranteed to get the payments for 20 years. Almost £800million has been set aside to cover the payments this year and costs are expected to rise to more than £1billion by 2020. Meanwhile thousands of homeowners across the country struggle to heat their homes and pay their winter bills.

Tory MEP Daniel Hannan called the scheme ‘upper class welfarism’. He added: ‘A system like this can be literally corrupting in that it makes an otherwise good person behave badly.’

A similar ‘cash for ash’ scandal in Northern Ireland has led to a political crisis there. Homeowners milked profits by turning ‘green’ heating to maximum and opening windows.

Today the Mail can reveal:

Green energy salesmen claim clients in England make up to £50,000 a year from the renewable heat incentive scheme (RHI);

Landowners are advised to make money by using woodchip-fuelled heating in old farmhouses as they are poorly insulated and use more energy;

Investigations into suspected RHI fraud rose last year;

The ‘green’ boilers are up to 20 per cent less efficient than hoped.

For six years wealthy homeowners and businesses have been pushed to switch oil and electric heaters to biomass boilers which get energy from woodchips or pellets, rotted trees, manure and sewage. The idea is to help the UK hit an EU target of getting 15 per cent of its energy from renewable sources by 2020. They are paid depending on how much heat is used. A cap of about 15 per cent of all the hours in the year exists to stop people keeping the heating on maximum all day.

But some users try to get as close to the cap as possible to maximise the payouts. Our undercover reporter, posing as a country estate employee, was encouraged by biomass salesmen to exploit the RHI.

‘What you want to do is get up as close to that [cap] in a year as you can because that’s where your maximum benefit’s going to be,’ one said. ‘You might increase your temperature in the pool by a degree or two or raise the temperature in the houses.’

He added: ‘If you’ve got an old farmhouse or cottages that aren’t very well insulated that’s better because you’re going to be using more energy, therefore you’re going to get more money back.’

The House of Schivas estate signed up to the RHI scheme more than four years ago and has claimed tens of thousands of pounds to use a woodchip boiler to heat the main house and the farm manager’s home. But it allegedly made most money on its pool.

‘The payback was quicker with the swimming pool because it was on all the time,’ former estate manager Mark Andrew told the Mail.

‘It was using heat all the time. It’s absolutely brilliant. Throughout the year it’s the same. Throughout winter and summer.’

The investigation by Ofgem, the Office of Gas and Electricity Markets, will examine if rules have been manipulated rather than any suspicion of fraud.